3.0 How thick is the brush replacement of art calligraphy?

The artistic calligraphy of 3.0 is 4 cm. According to relevant data, the pen body of the small pen is less than 2.0 cm, the diameter is less than 0.5 cm, and the small characters are written less than 2 cm. Medium-sized brush strokes are 2-3.5cm, with a diameter of 0.5- 1 and strokes of 2-5 cm; The stroke is 3.5cm, with a diameter of 1- 1.5cm, with a stroke of 5-8cm or more and a diameter of 1.5cm or more.